Mixed salts of aluminum

ABSTRACT

WHEREIN R is an organic acid radical of from 7 to 20 carbon atoms, and n has an average value of from 0.5 to 2.5. The compounds of the above description are useful as herbicides.   This invention discloses mixed salts of aluminum having the empirical formula

United States Patent Hokama [52] US. Cl 260/408, 260/448, 71/115 [51] Int. Cl. C09f 5/00, C09f 7/00 [58] Field of Search 260/408, 448; 71/115 [56] References Cited UNITED STATES PATENTS 3.708.522 l/l973 Le Suer 260/408 Primary Examiner-Elbert L. Roberts Attorney, Agent, or FirnzRobert J. Schwarz; Dietmar H. Olesch 1 Mar. 11, 1975 [57] ABSTRACT This invention discloses mixed salts of aluminum having the empirical formula wherein R is an organic acid radical of from 7 to 20 carbon atoms, and n has an average value of from 0.5 to 2.5. The compounds of the above description are useful as herbicides.

I 8 Claims, No Drawings OCH cl wherein R is an organic acid radical having from 7 to carbon atoms; and n has an average value of from 0.5 to 2.5. In a preferred embodiment of the present invention n has an average value of from about 1.0 to about 2.0.

The compounds of the present invention are useful as herbicides and possess the unexpected property of resisting leaching in the soil.

Weeds often grow near the soil surface whereas many beneficial plants have their roots deeper in the ground. Thus, to avoid injury to the benefical plants which may be partially sensitive to a herbicide, it is desirable to minimize leaching or downward movement of the herbicide in the soil. Furthermore, a basis for the preemergence action of herbicides is often the difference in depth between the planted crop seeds and the weed seeds on the surface of the soil. Crop seeds are generally planted one to three inches deep and are somewhat protected from chemicals applied to the soil surface, while weed seeds generally germinate only in the top one-fourth inch of the soil and are thus subject to a much higher concentration of the chemical. To maintain this difference in concentration of the chemical, it is desirable to have a herbicide which is resistant to leaching in the soil. The compounds of the present invention resist leaching to a high degree.

The compounds of the present invention can be prepared by reacting an aluminum salt of an organic acid having from 7 to 20 carbon atoms with an appropriate amount fo 2-methoxy-3,o-dichlorobenzoic acid according to the following equation:

Al(C ,-H OCH CI CO (R);,,', nHR wherein R and n are as heretofore described. This reaction can be effected by combining the reactants in an inert organic reaction medium such as benzene toluene or xylene and heating the reaction mixture at reflux for a period of from about 4 to about 24 hours. After this time the reaction mixture can be stripped of solvent under reduced pressure to yield the desired product.

The mixed aluminum salts of the present invention can also be prepared by reacting an inorganic water soluble aluminum salt such as aluminum nitrate, aluminum sulfate, aluminum chloride and the like with appropriate amounts of an alkali metal salt of 2-methoxy- 3.6-dichlorobenzoic acid and an alkali metal salt of an organic acid having from 7 to 20 carbon atoms according to the following exemplary equation:

Al (C H OCH Cl CO (R),,',, 3/2 Na SO wherein R and n are as heretofore described. This reaction can be effected by adding an aqueous solution of the inorganic aluminum salt to the appropriate stoichiometric mixture of the salts of the organic acids in an aqueous reaction medium. The resulting mixture can be heated at temperatures of from about 60 to about 95C for a period of up to several hours. After this time, the desired product can be recovered by filtration and can be used as such or can be further puritied by conventional means.

The sodium salts of the organic acids can also be prepared in situ by using a strong basic reaction medium such as an aqueous alkali metal hydroxide.

As previously indicated the R group is an organic acid radical having from 7 to 20 carbon atoms. suitable acids which can be used in the form oftheir alkali metal salts such as the sodium or potassium salt to prepare the compounds of this invention'and obtain the desired R group are aliphatic acids such as oenanthic acid, caprylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid and stearic acid; aromatic acids such as benzoic acid, toluic acid, ethylbenzoic acid, t-butylbenzoic acid, phthalic acid, isophthalic acid, 3-chlorobenzoic acid. 4- chlorobenzoic acid, 3,4-dichlorobenzoic acid, 2,4- dichlorobenzoic' acid, 2,4,6-trichlorobenzoic acid. 2-methyl-4-chlorobenzoic acid, phenylacetic acid, 3- chlorophenylacetic acid, 4-chlorophenylacetic acid. 2,4-dichlorophenylacetic acid, 3.4- dichlorophenylacetic acid, 2,4,5-trichlorophenylacetic acid, phenoxyacetic acid, 2,4-dichlorophenoxyacetic acid, 3,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid and the like.

The manner in which the compounds of the present invention can be prepared is more specifically illustrated in the following examples.

EXAMPLE 1 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6dichloroben2oic Acid and Stearic Acid of the Empirical Formula (C gH35O )2 Aluminum stearate, Al (C H O (43.8 grams; 0.05 mol), 2-methoxy-3,-dichlorobenzoic acid (1 L0 grams, 0.05 mol) and benzene (200 ml) were charged into a glass reaction flask equipped with a mechanical stirrer, thermometer and reflux condenser. The reaction mixture was heated at a temperature of about C until solution occurred. After this time, the reaction mixture was stripped of solvent under reduced pressure to yield the desired product as a solid having the empirical formula Al (C l-l OCH Cl CO (C H OQ EXAMPLE 2 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Stearic Acid of the Empirical Formula Al (C -H OCH Cl CO (C H O Aluminum stearate, al (C,,,H,, O (43.8 grams: 0.05 mol), 2-methoxy-3,o-dichlorobenzoic acid (22.l grams; 0.1 mol) and benzene (200 ml) were charged into a glass reaction flask equipped with a mechanical stirrer, thermometer and reflux condenser. The reaction mixture was heated at a temperature of about 80C until solution occurred. After this time, the reaction mixture was stripped of solvent under reduced pressure to yield the desired product as a solid having the empirical formula Al(C5HgOCH3ClgCOg)g (C gH 5O EXAMPLE 3 Preparation of a Mixed Salt of Aluminum, Z-Methoxy- 3,6-dichlorobenzoic Acid and Stearic Acid of the Empirical Formula AI(CH2OCH3CI2CO2)2 5 (C1BH35O2)05 A solution of 2-methoxy-3,6-dichlorobenzoic acid (11.05 grams; 0.05 mol) in benzene (150 ml) was placed into a glass beaker and aluminum stearate, Al(C, H O (17.55 grams; 0.02 mol) was added thereto. The mixture was heated on a steam bath with stirring until gellation occurred. The gelled product was then stripped of solvent to yield a solid product. This product was further dried in a vacuum oven at 100C under aspirator pressure. A portion of the resulting product (10 grams) was then charged with xylene (50 grams) into a flask equipped with a reflux condenser. The mixture was then heated at reflux to yield a solution of the desired product of the empirical formula 6 2 3 2 2)2.5 1s 35 2)0.5'

EXAMPLE 4 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Stearic Acid of the Empirical Formula Al(C H OCH Cl CO (C, H O

2-Methoxy-3,-dichlorobenzoic acid (1 1.05 grams; 0.05mol) and stearic acid (7.11 grams; 0.025 mol) were added to a solution of sodium hydroxide (3 grams; 0.075 mol) in water (50 ml). The mixture was heated to melt the stearic acid thereby forming a heterogeneous solution. This solution was then added to a solution of aluminum nitrate nonahydrate (9.38 grams; 0.025 mol) in water (100 ml) with vigorous stirring. Stirring was continued for a period of about 60 minutes to yield a solid product. This product was recovered by filtration, was washed with water and was dried under vacuum at 100C. Five grams of this product was then dissolved in xylene to yield a solution of the desired product of the empirical formula Al(C H OCH Cl- 2 2)2 is 3s 2)- 8 EXAMPLE 5 Preparation ofa Mixed Saltof Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Benzoic Acid of the Empirical Formula (C6H5CO2) 2-Methoxy-3.6-dichlorobenzoic acid (33.15 grams; 0.15 mol), benzoic acid (18.3 grams; 0.15 mol), sodium hydroxide (9 grams; 0.225 mol) and water (300 ml) were charged into a glass reaction vessel equipped with a mechanical stirrer and reflux condenser. The mixture was heated to 90C and a solution of aluminum sulfate octadecahydrate (24.99 grams; 0.0375 mol) in water (100 ml) was added with stirring. The mixture was reheated to 90C and was then allowed to cool to room temperature. The cooled mixture was then filtered to recover the desired product as a powdered solid having the empirical formula Al (C H OCH Cl- 2k (CGHCOZ)- EXAMPLE 6 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Octanoic Acid of the Empirical Formula Al (C H OCH Cl CO (C l'l O 2-Methoxy-3,o-dichlorobenzoic acid (33.15 grams; 87 percent assay; 0.15 mol), octanoic acid (21.6 grams; 0.15 mol), sodium hydroxide (9 grams; 0.225 mol) and water were charged into a reaction vessel equipped with thermometer and mechanical stirrer. The mixture was heated to a temperature of about 90C and a solution of aluminum sulfate octadecahydrate (24.99 grams: 0.0375 mol) in water (100 ml) was added thereto. The mixture was reheated to a temperature of about C and was then allowed to cool to room temperature. The solid formed was recovered by filtration; was washed with water and dried. The dried product was then refluxed in xylene to yield a solution ofthe desired product having the empirical formula Al (CGH2OCH3CI2CO2)2 (CSH1SO2)- EXAMPLE 7 Preparation ofa Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Toluic Acid of the Empirical Formula Al (C H OCH Cl O (i -4 3 2)2.5

2-Methoxy-3,6-dichlorobenzoic acid (0.04 mol), toluic acid (0.2 mol) sodium hydroxide (9.6 grams; 0.24 mol) and water (250 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture is heated to a temperature of about C and a solution of aluminum sulfate (0.04 mol) in water (100 ml) is added thereto. The mixture is then heated at about C for a period of about 60 minutes with continued stirring. After this time the reaction mixture is cooled to room temperature and is filtered to recover solid product. This solid is then washed with water and is dried to yield the desired product of the empirical formula A1 (C H OCH C- 2 2)0.5 6 4 a 2)2.5-

EXAMPLE 8 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Oenanthic Acid of the Empirical FOrmUla (C(;H2OCH;;CI202)2 0 8 l3 2)l.0

2-Methoxy-3,o-dichlorobenzoic acid (0.14 mol), oenanthic acid (0.07 mol) sodium hydroxide (8.4 grams; 0.21 mol) and water (250 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture is heated to a temperature of about 90C and a solution of aluminum sulfate (0.035 mol) in water ml) is added thereto. The mixture is then heated at about 90C for a period of about 45 minutes with continued stirring. After this time, the reaction mixture is cooled to room temperature and is filtered to recover solid product. This solid is then washed with water and is dried to yield the desired product of the empirical formula Al 6 2 3 2 2)2.0 (C6H13CO2)L0- EXAMPLE 9 Preparation of a Mixed Salt of Aluminum, 2-Methoxy- 3,6-dichlorobenzoic Acid and Caprylic Acid of the Empirical FQI'mula (C H2OCH3Cl2O )2 0 (C7H15CO2)L0 2-Methoxy-3,6-dichlorobenzoic acid (0.14 mol), caprylic acid (0.07 mol) sodium hydroxide (8.4 grams; 0.21 mol) and water (250 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture is heated to a temperature of about 85C and a solution of aluminum sulfate (0.035 mol) in water (100 ml) is added thereto. The mixture is then heated at about 85C for a period of about 60 minutes with continued stirring. After this time the reaction mixture is cooled to room temperature and is filtered to recover solid product. This solid is then washed with water and is dried to yield the desired product of the empirical formula Al (i 2 3 2 2)2.0 1 15 2)|.0-

EXAMPLE Preparation of a Mixed Salt of Aluminum, Z-Methoxy- 3,6-dichlorobenzoic Acid and t-Butylbenzoic Acid of the Empirical Formula Al (C H OCl-l Cl O (CGPI-ICJHQCO2)L5 2-Methoxy-3,6-dichlorobenzoic acid (0.1 1 mol), tbutylbenzoic acid (0.11 mol) sodium hydroxide (8.8 grams; 0.22 mol) and water (250 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture is heated to a tem perature of about 80C and a solution of aluminum sulfate (0.036 mol) in water (100 ml) is added thereto. The mixture is then heated at about 80C for a period of about 90 minutes with continued stirring. After this time, the reaction mixture is cooled to room temperature and is filtered to recover solid product. This solid is then washed and is dried to yield the desired product of the empirical formula Al (C H OCH Cl O ti t -t 9 2)1.5'

For practical use as herbicides the compounds of this invention are generally incorporated into herbicidal compositions which comprise an inert carrier and a herbicidally toxic amount of such a compound. Such herbicidal compositions, which can also be called formulations, enable the active compound to be applied conveniently to the site of the weed infestation in any desired quantity. These compositions can be solids such as dusts, granules, or wettable powders; or they can be liquids such as solutions, aerosols, or emulsifiable concentrates.

For example, dusts can be prepared by grinding and blending the active compound with a solid inert carrier such as the talcs, clays, silicas, pyrophyllite, and the like. Granular formulations can be prepared by impregnating the compound usually dissolved in a suitable solvent, onto and into granulated carriers such as the attapulgites or the vermiculites, usually of a particle size range of from about 0.3 to 1.5 mm. Wettable powders, which can be dispersed in water or oil to any desired concentration of the active compound, can be prepared by incorporating wetting agents into concentrated dust compositions.

In some cases the active compounds are sufficiently soluble in common organic solvents such as kerosene or xylene so that they can be used directly as solutions in these solvents. Frequently, solutions of herbicides can be dispersed under supera tmospheric pressure as aerosols. However, preferred liquid herbicidal compositions are emulsifiable concentrates, which comprise an active compound according to this invention and as the inert carrier. a solvent and an emulsifier. Such emulsifiable concentrates can be extended with water and/or oil to any desired concentration of active compound for application as sprays to the site of the weed infestation. The emulsifiers most commonly used in these concentrates are nonionic or mixtures of nonionic with anionic surface-active agents. With the use of some emulsifier systems an inverted emulsion (water in oil) can be prepared for direct application to weed infestations.

A typical herbicidal composition according to this invention is illustrated by the following example, in which the quantities are in parts by weight.

EXAMPLE 11 Preparation of a Dust Product of Example 1 Powdered Tale The above ingredients are mixed in a mechanical grinder-blender and are ground until a homogeneous. free-flowing dust of the desired particle size is obtained. This dust is suitable for direct application to the site of the weed infestation.

The compounds of this invention can be applied as herbicides in any manner recognized by the art. One method for the control of weeds comprises contacting the locus of said weeds with a herbicidal composition comprising an inert carrier and as an essential active ingredient, in a quantity which is herbicidally toxic to said weeds, a compound of the present invention. The concentration of the new compounds of this invention in the herbicidal compositions will vary greatly with the type of formulation and the purpose for which it is designed, but generally the herbicidal compositions will comprise from about 0.05 to about 95 percent by weight of the active compounds of this invention. ln a preferred embodiment of this invention, the herbicidal compositions will comprise from about 5 to about 75 percent by weight of the active compound. The compositions can also comprise such additional substances as other pesticides, such as insecticides, nematocides, fungicides, and the like; stabilizers, spreaders, deactivators, adhesives, stickers, fertilizers, activators, synergists, and the like.

The compounds of the present invention are also useful when combined with other herbicides and/or defoliants, dessicants, growth inhibitors, and the like in the herbicidal compositions heretofore described. These other materials can comprise from about 5 percent to about 95 percent of the active ingredients inthe herbicidal compositions. Use of combinations of these other herbicides and/or defoliants, dessicants, etc. with the compounds of the present invention provide herbicidal compositions which are more effective in controlling weeds and often provide results unattainable with separate compositions of the individual herbicides. The other herbicides, defoliants, dessicants and plant growth inhibitors, with which the compounds of this invention can be used in the herbicidal compositions to control weeds, can include chlorophenoxy herbicides such as 2,4-D, 2,4,5-T, MCPA, MCPB, 4(2,4-DB), 2,4- DEB, 4-CPB, 4-CPA, 4-CPP, 2,4,5-TB, 2,4,5-TES, 3,4- DA, silvex and the like; carbamate herbicides such as lPC, ClPC, swep, barban, BCPC, CEPC, CPPC, and the like; thioearbamate and dithiocarbamate herbicides such as CDEC, metham sodium, EPTC, diallate, PEBC, perbulate, vernolate and the like; substituted urea herbicides such as norea, siduron, dichloral urea, chloroxuron, cycluron, fenuron, monuron, monuron TCA, diuron, linuron, monolinuron, neburon, buturon, trimetu ton and the like; symmetrical triazine herbicides such as simazine, chlorazine, atraone, desmetryne, norazine, ipazine, prometryn, atrazine, trietazine, simetone, prometone, propazine, ametryne, and the like; chloroacetamide herbicides such as alpha-chloro-N, N- dimethylacetamide, CDEA, CDAA, alpha-chloro-N- isopropylacetamide, 2-chloro-N'isopropylacetanilide, 4-(chloroacetyl)morpholine, l- (chloroacetyl)piperidine, and the like; chlorinated aliphatic acid herbicides such as TCA, dalapon, 2,3- dichloropropionic acid, 2,2,3-TPA and the like; chlorinated benzoic acid and phenylacetic acid herbicides such as 2,3,6-TBA, 2,3,5,6-TBA, tricamba, amiben, fenac, PBA, 2-methoxy-3,6-dichlorophenylacetic acid, 3-methoxy-2,6-dichlorophenylacetic acid, 2-methoxy- 3,5,6-trichlorophenylacetic acid, 2,4-dichloro-3- nitrobenzoic acid and the like; and such compounds as aminotriazole, maleic hydrazide, phenyl mercuric acetate, endothal, biuret, technical chlordane, dimethyl 2,3,5,6-tetrachloroterephthalate, diquat, erbon, DNC, DNBP, dichlobenil, DPA, diphenamid, dipropalin, trifluralin, solan, dicryl, merphos, DMPA, DSMA, MSMA, potassium azide, acrolein, benefin, bensulide, AMS, bromacil, 2-(3,4-dichlorophenyl)-4-methyll,2,4-oxadiazolidine-3,S-dione, bromoxynil, cacodylic acid, CMA, CPMF, cypromid, DCB, DCPA, dichlone, diphenatril, DMTT, DNAP, EBEP, EXD, HCA, ioxynil, IPX, isocil, potassium cyanate, MAA, MAMA, MCPES, MCPP, MH, molinate, NPA, OCH, paraquat, PCP, picloram, DPA, PCA, pyrichlor, sesone, terbacil, terbutol, TCBA, brominil, CP-50l44, H-l76-1, H-732, m-290l, planavin, sodium tetraborate, calcium cyanamid, DEF, ethyl xanthogen disulfide, sindone, sindone B, propanil and the like.

Such herbicides can also be used in the methods and compositions of this invention in the form of their salts, esters, amides, and other derivatives whenever applicable to the particular parent compounds.

Weeds are undesirable plants growing where they are not wanted, having no economic value, and interfering with the production of cultivated crops, with the growing of ornamental plants, or with the welfare of livestock. Many types of weeds are known, including annuals such as pigweed, lambsquarter, foxtail, crabgrass, wild mustard, field pennycress, ryegrass, goose-grass, chickweed, wild oats, velvet leaf, purseland, barnyard grass, smartweed, knotweed, cocklebur, wild buckwheat, kochia, medic, corn cockle, ragweed, sowthistle, coffee-weed, croton, cuphea, dodder, fumitory, groundsel, hemp nettle, knowel, spurge, spurry, emex, jungle rice, pondweed, dog fennel, carpetweed, morning glory, bedstraw, ducksalad, and naiad; biennials such as wild carrot, matricaria, wild barley, campion, chamomile, burdock, mullein, roundleaved mallow, bull thistle, hounds-tongue, moth mullein, and purple star thistle; or perennials such as white cockle, perennial rye-grass, quackgrass, Johnson grass, Canada thistle, hedge bindweed, Bermuda grass, sheep sorrel, curly dock, nutgrass, field chickweed, dandelion, campanual, field bindweed, Russian knapwee, mesquite, toadflax, yarrow, aster, gromwell, horsetail, ironweed, sesbania, bulrush, cattail and winter-Cress.

Similarly, such weeds can be classified as broadleaf or grassy weeds. It is economically desirable to control the growth of such weeds without damaging beneficial plants or livestock.

The new compounds ofthis invention are particularly valuable for weed control because they are toxic to many species and groups of weeds while they are relatively non-toxic to many beneficial plants. The exact amount of compound required will depend on a variety of factors, including the hardiness of the particular weed species, weather. type of soil, method of application, the kind of beneficial plants in the same area, and the like. Thus, while the application of up to only about one or two ounces of active compound per acre may be sufficient for good control of a light infestation of weeds growing under adverse conditions, the application of ten pounds or more of active compound per acre may be required for good control of a dense infestation of hardy perennial weeds growing under favorable conditions.

The herbicidal toxicity of the new compounds of this invention can be illustrated by many of the established testing techniques known to the art, such as preand postemergence testing.

The herbicidal activity of the compounds of this invention was demonstrated by experiments carried out for the pre-emergence control of a variety of weeds. In these experiments small plastic greenhouse pots filled with dry soil were seeded with the various weed seeds. Twenty-four hours or less after seeding the pots were sprayed with water until the soil was wet and the test compounds formulated as aqueous emulsions of acetone solutions containing emulsifiers were sprayed at the indicated concentrations on the surface of the soil.

After spraying, the soil containers were placed in the greenhouse and provided with supplementary heat as required and daily or more frequent watering. The plants were maintained under these conditions for a period of from 15 to 21 days, at which time the condition of the plants and the degree of injury to the plants was rated on a scale of from 1 to 10 as follows: 0 no injury, 1,2 slight injury, 3,4 moderate injury, 5,6 moderately severe injury, 7,8,9 severe injury and i0 death. The effectiveness of these compounds is demonstrated by the followingdata:

TABLE I INJURY RATING Prod of Ex. I Prod. of Ex. 2

Rate Lbs/Acre Rate Lbs/Acre Weed Species 4 l 0.25 4 l 0.25

Yellow Nutsedge l0 l0 l0 l0 l0 0 Wild Oats l0 l0 8 l0 l0 7 .limsonweed i0 10 l0 l0 l0 l0 Velvetleaf l0 l0 9 -l0 l0 8 Johnson grass l0 l0 5 l0 l0 6 Pigweed l0 l0 l0 l0 l0 l0 Mustard l0 l0 l0 l0 l0 9 Yellow Foxtail l0 9 6 l0 9 6 Watergrass l0 9 6 l0 9 7 Crabgrass l0 9 6 l0 l0 7 Cheatgrass 10 I O 8 l0 9 7 Morning glory l0 l0 l0 l0 l0 9 The herbicidal activity of the compounds of this invention was also demonstrated by experiments carried out for the post-emergence control of a variety of weeds. In these experiments the compounds to be tested were formulated as aqueous emulsions and sprayed at the indicated dosage on the foliage of the various weed species that have attained a prescribed size. After spraying the plants were placed in a greenhouse and watered daily or more frequently. Water was not applied to the foliage of the treated plants. The severity of the injury was determined 10 to 15 days after treatment and was rated on the scale of from 0 to 10 heretofore described. The effectiveness of these compounds is demonstrated by the following data:

TABLE II lNll/RY RATING pound in the water eluant indicated the amount of test compound which had passed through the soil column and IS a measure of the degree of leaching of the test l'rotl. ul lax. l Prod. of Ex. 2 ompound in soil. For comparative purposes. the iden- Rille llbs/Am Rule Lbs/AC"? 5 Meal leaching experiment was carried out using the di- Weed Specles 1 1/4 l/lh 1 H4 1 methylamine salt of 2-methoxy-3,o-dichlorobenzoie Venn, Nulsedge 2 U 3 0 0 acid. The result of these experiments are shown in Wild Oats 2 l o 0 o 0 Table III.

TABLE Ill 7! Test Compound Present in the Amount of Test Water Eluant Based Compound Applied on Amount Applied Physical State to the Soil Expressed to the Soil Expressed Test Compound on Application as Dicamba* as Dicamba* Product of Example I Solid Powder 3.57 X l0 grams 0.4 Product of Example 2 Solid Powder 3.39 X 10 grams 2.8 Product of Example 3 Xylene Solution 3.04 X 10" grams l5.l Product of Example 4 Xylene Solution 3.02 X 10 grams l6.8 Product of Example 5 Solid Powder 3.0 X grams 01 Product of Example 6 Xylene Solution 2.99 X 10 grams 29.4 Dimethylamine Salt of 2Methoxy3.6- dichlorobenzoic Acid Ethyl Ether Solution 3.l0 X 10"" grams 103.6

*Dieamba Z-methoxy-3,o-dichlorohenzoic acid Jimsonweed 10 10 7 10 l0 l0 1 Claim; Pigweed l0 l0 7 10 IO ll] johnsongmss 3 O 0 5 2 O 1. A mixed salt of aluminum having the empirical for- Bindweed l0 9 9 l0 l0 9 mula Mustard 9 8 6 s 7 4 Yellow Foxtail 3 0 U 4 0 0 Watergrass 8 2 0 9 O 0 C rabgrass l 0 0 2 0 0 Morning glory l0 l0 4 l0 l0 5 3 The resistance to leaching of the compounds of the present invention was demonstrated in experiments wherein the migration of the compounds of this invention through soil was measured. in these experiments a plastic column was packed with soil which had previously been dried and passed through a 30 mesh screen. The column was packed to a soil depth of 3 inches. The test compounds were then applied to the soil surface in the form of a solid powder or xylene solution and water (284 ml) equivalent to 6 inches of rainfall was then poured on top of the soil column in a single addition. The column was allowed to stand for a period of 24 hours during which time the water slowly eluted from the bottom ofthe column was collected. The water eluant was then analyzed for the amount of test compound present. The aqueous solution was concentrated and hydralyzed with 50 percent aqueous hydrochloric acid. The acidified solution was extracted with chloroform and analyzed by quantitative infra-red analysis as 2- methoxy-3,o-dichlorobenzoic acid. The stoichiometric conversion and subsequent analysis for the test comwherein R is an organic acid radical of from 7 to 20 carbon atoms and n has an average value of from 0.5 to 2.5 

1. A MIXED SALT OF ALUMINUM HAVING THE EMPIRICAL FORMULA
 1. A mixed salt of aluminum having the empirical formula
 2. A salt of claim 1 wherein n is 1 .
 3. A salt of claim 1 wherein n is 2 .
 4. A salt of claim 1 wherein R is a stearic acid radical.
 5. A salt of claim 1 wherein R is a benzoic acid radical.
 6. A salt of claim 1 wherein R is a caprylic acid radical.
 7. A salt of claim 1 wherein R is a toluic acid radical. 